Heretofore, copolymers have been prepared by reacting alkali metal terminate organic polymers free of silicon atoms with cyclic siloxanes. (See U.S. Pat. Nos. 3,483,270 and 3,051,684 to Bostick and Morton et al, respectively.) However, neither of these references disclose the formation of silylated polymers by reacting alkali metal terminated organic polymers with silicon compounds having aliphatic unsaturation to form organic polymers containing silicon atoms. Moreover, these references do not disclose silylated organic-organopolysiloxane block copolymers or a method for preparing the same.
Also, U.S. Pat. No. 3,956,419 to Murray discloses a slurry polymerization of styrene and divinylbenzene in the presence of an anionic initiator and thereafter terminating the slurry polymerization with a suitable terminating agent which imparts groups that are reactive with a silicone rubber when its cure is effected.
Murray discloses forming a carbanion containing organic polymer by polymerizing a monomer having carbon-to-carbon double bonds in the presence of a carbanion forming catalyst and then reacting the organic polymer with a terminating agent. It does not disclose reacting an alkali metal terminated silylated organic polymer or silylated organic silicone copolymers with a terminating agent.
U.S. Pat. No. 3,468,972 to Hsieh discloses reacting lithium terminated organic polymers with polyfunctional treating agents to produce a maximum of branching or coupling as the case may be. This reference does not disclose reacting a silylated organic polymer with a silane which is free of aliphatic unsaturation and has at least one functional group which is capable of reacting with the carbanion and thereby terminating the silylated organic polymer.
Therefore, it is an object of this invention to prepare silylated organic polymers. Another object of this invention is to provide silylated organic-organopolysiloxane block copolymers. Still another object of this invention is to provide a method for preparing carbanion free silylated organic polymers. A further object of this invention is to provide a method for preparing silylated organic-organopolysiloxane block copolymers.